Gaussian free field level line
= Gaussian free field level line
{c}
A continuum field level line is specified by the harmonic boundary heights it creates and the conditional zero-boundary field remaining on each side. Since a <Continuum Gaussian free field> is a random distribution, this is not the pointwise set of its zeros. For the height jump appropriate to the Green-function normalization, the zero-height line between opposite Dirichlet heights is chordal $\operatorname{SLE}_4$.